In the model, increasing greenhouse gas emissions lead to a warmer surface and, at the same time, a colder stratosphere.
However, UN weather and climate agency said the hole was "no cause for alarm" and was larger due to colder stratosphere but will shrink again – ozone depletion is seasonal, starting each year during the Antarctic spring and peaking between mid-September and early October.
The survey's results were announced yesterday by the Pasadena laboratory and the National Aeronautics and Space Administration's Goddard Space Flight Center in Greenbelt, Md. Most Arctic winters in the last decade brought unusually low ozone coincident with an unusually cold stratosphere, according to the World Meteorological Organization.
This year, a colder than usual stratosphere widened the hole to a peak of 28.2 million square km (10.9 million square miles) on 2 October, bigger than Canada and Russia put together.
The model reproduces the latitudinal temperature gradients quite well: a cold winter lower stratosphere, an elevated winter stratopause, a warm summer stratopause, and a cold summer mesopause.
Baumgartner, who is famous for stunts such as jumping off the Petronas Towers, is seen in the special pressure suit he must wear to stay alive in the thin air and extreme cold of the stratosphere.
The abundance ratio of water is around 7. Ethane and acetylene tend to condense in the colder lower part of stratosphere and tropopause (below 10 mBar level) forming haze layers, which may be partly responsible for the bland appearance of Uranus.
Whether the cold snap in the stratosphere "is related to it being warmer than it typically is lower down is intriguing," Dr. Livesey said, "but the connection has yet to be made".
The ozone hole that appears over Antarctica fluctuates in size, normally reaching its widest in the polar spring as extreme cold temperatures in the stratosphere and the return of sunlight unleash chlorine radicals that destroy ozone.
During the winter, when the stratosphere is cold and dense, the charged mesons are more likely to interact with atoms in the atmosphere and produce secondary low energy particles which are picked up by the surface detectors.
His explanation for the ozone hole, based on laboratory tests, involves "chemistry of a most unusual character" in which, in the extreme cold of the Antarctic stratosphere, nitric acid and water form crystals that drop out of the atmosphere as nitric acid ice, he said.
